It is standard practice to cut a circular groove with a single point tool fed slowly into a workpiece as the workpiece is rotated at high speed. This present day method is time-consuming and, since all of the cutting is done by a single cutting element, requires frequent replacement of the cutting element.
In accordance with this invention, the groove is cut by means of a milling cutter. The workpiece remains stationary and the cutter, rotating at high speed, is feed into the workpiece to full groove depth. Then, with the cutter continuing to rotate at high speed, the workpiece is turned once 360.degree. at a relatively slow speed to completely mill a circular groove.
More specifically, the milling cutter comprises a pair of circular cutter bodies clamped to opposite sides of a spacer. Each cutter body has circumferentially spaced slots in its periphery in which cutting elements are mounted. The cutting elements are capable of simultaneously cutting a pair of axially spaced grooves in the side edges of the periphery of a circular disk such, for example, as the stator of an alternator for an automobile. Some of the cutting elements are notching elements which cut grooves, while others are chamfering elements. Of the chamfering elements, some cut a chamfer on the side edges of the grooves and others cut a chamber on the radially outer edges of the grooves.
These and other objects of the invention will become more apparent as the following description proceeds, especially when considered with the accompanying drawings.